The value of Mewtwo cards varies, with the most valuable cards being those with printing errors or from earlier collectionsable to fetch thousands of dollars
If you Fusion Summon a monster this turn with "Overload Fusion", using 6 or more monsters as material, that monster can attack a number of times each Battle Phase this turn, up to the number of monsters used as its Fusion Materials
3 Mewtwo Star: Holon Phantoms (Ultra Rare) $249.99+ A Shining Example Holon Phantoms is one of the crown jewels of the EX era of Pokemon, featuring a gorgeous array of "Star" shiny Pokemon, like this Mewtwo
The exception to this rule are cards with "partner with" which can only partner with a single specified card
She's cheap, draws you cards, and then if she sticks around she gets huge and starts thwacking everyone for chunks of non-combat damage
+1: Attach this Equipment to up to one target creature you control